In many industrial applications such as in refineries, power generation facilities, petrochemical facilities and other general industries, on-site flange re-facing is an integral part of any plant turn-around or outage/shut down for many years.
Traditionally, the machining of large diameter flanges is done by very heavy and costly equipment operated by contractors. In many instances, the need to do actual machining is not always the case. In this regard, performing run-out checks on the flange-face surfaces to determine surface variations from original specification tolerances reveals that there is no need for machining. Oftentimes run-out checks find that flange completely undamaged with the source of the problem being unrelated to the flange, such as gasket failure. However, this is usually discovered too late after the contractor costs and significant plant equipment costs have already been incurred.
The present invention offers a quick and cost-effective alternative for performing run-out checks on flanges and determining the need for flange re-facing. Because of its compact size and ease of mobilization, the present invention can be operated by workers. Further, the present invention obviates the need for hiring a contractor and incurring other costs associated with mobilizing equipment to the facility.
The present invention weighs an estimated 150 pounds when fully extended to measure a 100-inch diameter flange. For measuring a 20-inch flange, the weight of the present invention is approximately 50 pounds. In comparison, a traditional flange re-facing machine in production today, capable of doing the same measurements on a 100-inch diameter flange weighs approximately 2000 pounds. As such, a heavy lifting equipment is required to mobilized conventional flange machines.
In contrast, the present invention can be disassembled and contained in 3 separate cases weighing 75 pounds each and can be mobilized by two people carrying the cases.
The present invention mounts unto the outside diameter of flanges, similar to the traditional outside diameter flange re-facing machine, with four contact points to the flange diameter (legs). There is an arm similar to a pointer with a surface variation indicator located at the end mounted in line with the face of the flange to be checked. This arm is mounted to a guide ring and bearing housing which can rotate 360 degrees to perform measurements on the flange face. A transmission takes a rotation input and transmit a rotational output which drives the measuring arm.